While food intolerance usually affects the organs of the gastrointestinal tract, allergic reactions affect the entire immune system. At first glance, symptoms can be similar, so it’s important to know whether a food allergy is present so that measures can be taken against anaphylaxis.

Causes

Lack of digestive enzymes; foods irritating the digestive system

Food proteins (allergens)

An intolerance is often caused by enzyme defects, as in the case of lactose intolerance. A food allergy is caused by an adverse reaction to food proteins on the part of the immune system. Common food allergens include peanuts, tree nuts, fish, egg and milk.

Mechanism

Non-immune-mediated (Enzymatic; Pharmacological)

Immune-mediated ( Immunoglobulin, or IgE)

With food intolerance, an enzyme may be missing or diminished.

The mechanism of food allergies involves the immune system. There are two main phases:

1) Sensitization phase: IgE antibodies are produced in reaction to allergenic proteins and attach to the surface of effector cells, known as mast cells. Once attached, they are ready to react to the offending food.

A food intolerance can be painful, but an allergy can be lethal. Anaphylactic shock, or anaphylaxis, is a life-threatening condition that can cause a sudden drop in blood pressure and impair breathing. Such reactions are unpredictable and therefore all the more dangerous. As there is no treatment for a food allergy, allergic individuals have only one option: strict avoidance of foods with ingredients to which they are allergic.